You may not notice it with Interlace-pictures, because it's all a blur basically, but PAL-emulation (which AFAIK none of the PC-pixeltools even supports!) is still *way* inadequate...
Cruzer, right I said this too, an all round editor would need to feature a simple line based VICII "emulator" (concentrating on the output only), and possibility to change any register on any line. Ofcourse skipping the hairy stuff like d011 tricks, spritecrunch, d018 change should be possible on each line, sprite plexing should come for free just like turning off borders, etc.
when this is done the hard thing is to find out & realize a clever user interface to draw into this :)